Medical Subject Headings is a comprehensive controlled vocabulary for the purpose of indexing journal articles and books in the life sciences; it can also serve as a thesaurus that facilitates searching. Created and updated by the United States National Library of Medicine, it is used by the MEDLINE/PubMed article database and by NLM's catalog of book holdings. MeSH is also used by ClinicalTrials.gov registry to classify which diseases are studied by trials registered in ClinicalTrials.gov.
MeSH was introduced in 1963. The yearly printed version was discontinued in 2007 and MeSH is now available online only. It can be browsed and downloaded free of charge through PubMed. Originally in English, MeSH has been translated into numerous other languages and allows retrieval of documents from different languages.
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Medical Subject Headings is a comprehensive controlled vocabulary for the purpose of indexing...
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MeSH is the National Library of Medicine's controlled vocabulary
thesaurus. It consists of sets of terms naming descriptors in a
hierarchical structure that permits searching at various levels of
specificity.
MeSH descriptors are arranged in both an alphabetic and a
hierarchical structure. At the most general level of the hierarchical
structure are very broad headings such as "Anatomy" or "Mental
Disorders." More specific headings are found at more narrow levels of
the eleven-level hierarchy, such as "Ankle" and "Conduct Disorder."
There are 24,767 descriptors in 2008 MeSH. In addition to these
headings, there are more than 172,000 headings called Supplementary
Concept Records (formerly Supplementary Chemical Records) within a
separate thesaurus. There are also over 97,000 entry terms that assist
in finding the most appropriate MeSH Heading, for example, "Vitamin C"
is an entry term to "Ascorbic Acid."

Medical Subject Headings is a comprehensive controlled vocabulary for the purpose of indexing journal articles and books in the life sciences; it can also serve as a thesaurus that facilitates searching. Created and updated by the United States National Library of Medicine, it is used by the MEDLINE/PubMed article database and by NLM's catalog of book holdings. MeSH is also used by ClinicalTrials.gov registry to classify which diseases are studied by trials registered in ClinicalTrials.gov.
MeSH was introduced in 1963. The yearly printed version was discontinued in 2007 and MeSH is now available online only. It can be browsed and downloaded free of charge through PubMed. Originally in English, MeSH has been translated into numerous other languages and allows retrieval of documents from different languages.